Field of the Invention
The present invention relates to the field of display technologies, and particularly, to an array substrate based on an Advanced-Super Dimensional Switching (AD-SDS) mode and a method of manufacturing the same, and a liquid crystal display screen.
Description of the Related Art
An Advanced-Super Dimensional Switching (AD-SDS) technology is a core technology for a plane electric field and a wide angle of view, where a multi-dimensional electric field is formed by parallel electric fields generated at edges of pixel electrodes within a same one plane and longitudinal electric fields generated between pixel electrode layers and common electrodes, so that all liquid crystal molecules which are located in various orientations between the pixel electrodes and directly above the electrodes within a liquid crystal cell can be rotated and deflected, thereby improving working efficiency of liquid crystals in a plane orientation system and increasing light transmission efficiency. The Advanced-Super Dimensional Switching technology can improve quality of a picture displayed by a TFT-LCD (thin film transistor-liquid crystal display) screen, and has advantages such as a high light transmittance, a wide angle of view, a high aperture ratio, low color shift, a low response time, no squeezed water ripple and the like.
A common electrode is always required for operations of the TFT liquid crystal display screen based on the AD-SDS display mode. For a TFT liquid crystal display screen where the common electrode is supplied with a direct current level, a voltage on the common electrode keeps in a stable level under an ideal state. In a practice display operation, however, since signals on gate lines and data lines change, the voltage on the common electrode will be often affected by coupling capacitances between the common electrode and the gate lines and the data lines, and thus cannot be maintained in a stable level. In case of a smaller sized display screen, the common electrode has a smaller size and has smaller overlapped areas with the gate lines and the data signal lines, thus the common electrode has a lower resistance value and a smaller parasitic capacitance value, and an impact to the potential of the common electrode is also smaller, thereby the voltage of the common electrode can be maintained better and has a good uniformity in the entire panel.
FIG. 1 shows a schematic structural diagram of a TFT liquid crystal display screen in the prior art, and FIG. 2(a)˜FIG. 2(e) show flowcharts of processes of manufacturing the TFT liquid crystal display screen in prior art. As shown in FIGS. 1 and 2, the TFT liquid crystal display screen comprises: a substrate 101, a common electrode 102, a gate layer 103, an layer of active material and source-drain electrodes 104, a passivation layer 105, and a pixel electrode 106. As can be seen from FIG. 2(b), through etching processes, the gate layer 103 is formed with a gate line 1031, a common electrode signal line 1032 above the common electrode and a through-hole region 1033 below the common electrode. A common electrode signal, after being inputting from an external input point, is transmitted through the common electrode signal line 1032 in a horizontal direction between pixel units in the horizontal direction, and is transmitted in a vertical direction, that is, between upper and lower pixel units, to the through-hole region 1033 below the common electrode through ITO material of the common electrode 102, and then is transmitted to a next row of pixel units through a jumper connecting the through-hole region 1033 and a next row of common electrode signal lines. The ITO material is usually selected for the common electrode 102, a sheet resistance of the ITO, however, is generally several hundreds of times of that of a metal layer. Since the common electrode signal line 1032 between common electrodes for a plurality of pixel units in the horizontal direction is formed from the gate layer 103, which is usually composed of a metal material, the resistance value of the common electrode in the horizontal direction, that is, a resistance value of the common electrode signal line between common electrodes for the plurality of pixel units in the horizontal direction, is much less than that of the common electrode signal line in the vertical direction, that is, between the common electrode signal line and the through-hole region. A voltage signal of a common electrode is transmitted through the common electrode signal line in horizontal direction, and through the common electrode in the vertical direction to the through-hole region, the common electrode signal transmitted to the through-hole region is transmitted to the common electrode signal line of a pixel unit therebelow through a jumper, which is used to connect the through-hole region and the common electrode signal line of the pixel unit therebelow, and which is composed of a pixel electrode layer, that is, a ITO layer. Thus, when the liquid crystal display screen has a larger size, the common electrode has a larger size and has a larger overlapped area with the gate lines and the data signal lines, thus the total impact to the common electrode is greater, and due to the larger size, the voltage of the common electrode far away from the input point for inputting the common electrode signal is not easy to be recovered after being impacted, which will result in a deflection voltage for liquid crystals of pixels, causing a difference in displayed color. Further, since human eyes are more sensitive to green color, some displayed patterns, when viewed by the human eyes, are pictures which are partial green on the display screen as a whole. Therefore, there is a need to reduce the resistance value of the common electrode in order to reduce the phenomenon of the partial green picture.